My boyfriend Alex and I are sweating our way through an ­after-dinner sauna on one of Sweden's most westerly, d­eserted islands; part of a group known collectively as the Weather Islands (Väderöarna). We've been here a few hours, and we've already met the only permanent resident, handyman Ingmar, and his close friends – a family of swans; we've slipped and skidded over this sparse collection of rocks, a pilot ­station until 1967, with its handful of red timber lodgings that are now used as holiday homes. And we have had a lovely, simple dinner at the island's guest house, where we're staying. A plate of beautifully fresh mussels, crayfish and prawns, followed by a fillet of meaty cod and a light berry parfait.

As the sauna's temperature rises, Alex decides on a dip in the biting midnight sea. "What's it like?" I ask, shivering in a towel. "Crisp," he pants, "fresh," then rushes back into the sauna.

It's an apt description of our seafood tour. We are struck by Sweden's cleanliness, by the pure air, the fresh fish. Our first destination is a tiny island called ­Klädesholmen, so we drive south from Gothenburg City airport through the frost-tipped countryside.

We arrive at our floating hotel, Salt & Sill, where we are greeted by owner Patrick Hermansson. This area has long been known for its herring industry, and so we join Patrick and get pickling. We mix the strong, tart herring fillets with cream, whisky and hickory smoke extract. The fish tastes like charred wood soaked in alcohol – in a good way.

There's more herring in the evening, at the hotel's restaurant, where our starter is three ­varieties of the fish paired with warming shots of schnapps. We're having the lobster menu (around £40 a person), so the next course is a lobster salad, followed by a very tender lobster tail with baked tomatoes and ­asparagus. After a rich chocolate dessert, we roll off to bed.

The next day we head to the clear waters of Grebbestad which is, we're told, the area that supplies most of the country's oysters and crayfish. We meet Per Karlsson as he arrives back from one of his fishing tours with an armful of oysters. He shows us how to open them – holding the shell in your left hand, a knife in your right, and trying not to damage the muscle inside. Per advises us to chew the oyster rather than just ­swallow it, and to skip the usual squeeze of lemon. The taste is slightly metallic, packed with minerals.

Then it's across the bumpy sea to the Weather Islands where that perfect dinner is followed, the next morning, by the most deliciously salty bacon and eggs I've tasted. With Alex and those swans for company, I could be happy here for months.

Getting there Ryanair flies from London ­Stansted to Gothenburg City, from £9.99 each way ­ (ryanair.com/en).

Stay atSalt & Sill, £140 per room per night. A visit to the Weather Islands, including accommo­dation and meals, costs from £158 per person in a double room; email info@vaderoarna.com or call 00 46 525 32001. Oyster safari, run by Per ­Karlsson, around £60 per person;. For more ­information, go to westsweden.com/.